Everton’s positions in the years before Moyes was appointed were 15th, 17th, 14th, 13th, 16th and 15th. You were the definition of relegation battlers.
He had one season where he struggled early on and then turned you into a team who was always in or around the European places. After he left, you‘ve steadily regressed back to being relegation candidates again, although Dyche does look as though he’s now moving you in the right direction.
As for West Ham, he initially took over with them in the relegation zone and kept them up (finishing 13th). He then took over again with them one point above the relegation zone and again kept them up (he only managed half the season when they finished on 39 points). Since then, they’ve finished 6th, 7th, 14th (but won a European trophy) and are currently again sitting 6th. It’s a quite astonishing job he’s done there.